An MI is more likely to occur early in the day, due to an increase in catecholimines. Aspirin, givin during an MI might actually help lyse the clot. There is an artery in the heart known as the widow maker, which is the cause if most deadly MI's. So I suppose the human heart is flawed.

During an MI, time is life. if the person is not breathing, and you know CPR, begin it immediately and call for help. If you do not know CPR, check for a patent airway, tilt the head back, and if there is no breathing--administer two breaths. If there is no heartbeat, give fifteen compressions, and two more breaths. Continue this pattern until help arrives or the person begins breathing on thier own.

Different people have different symptoms. While one person may have crushing chest pain, another might have a shortness of breath and back pain. If you, or someone you know thinks they may be having an MI, consult with a doctor.